use strict;
use warnings;
use Regexp::List;

my @words = qw!bob fred frederic ann anne annie!;
my $target = <<DATA;
This list contains Bob, Frederic, Fred, Robert, Annette and Ann.
And this list conatins Fred and Frederic.
DATA

my $match = Regexp::List->new (modifiers => 'i')->list2re (@words);
my @matches = $target =~ /($match)/g;

print "@matches";